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81.
In this study, we demonstrated that human type-5 adenovirus infected the brain of the teleost fish, medaka (Oryzias latipes), in vivo. Injection of adenoviral vector into the mesencephalic ventricle of medaka larvae induced the expression of reporter genes in some parts of the telencephalon, the periventricular area of the mesencephalon and diencephalon, and the cerebellum. Additionally, the Cre-loxP system works in medaka brains using transgenic medaka carrying a vector containing DsRed2, flanked by loxP sites under control of the β-actin promoter and downstream promoterless enhanced green fluorescent protein (EGFP). We demonstrated that the presence of green fluorescence depended on injection of adenoviral vector expressing the Cre gene and confirmed that EGFP mRNA was transcribed in the virus-injected larvae.  相似文献   
82.
83.
The presence of immunoreactive porcine brain natriuretic peptide in rat tissues was studied with a specific radioimmunoassay for porcine brain natriuretic peptide-26. The cross-reactivity of the antiserum used was less than 0.001% with rat atrial natriuretic peptide, rat brain natriuretic peptide-32 and rat brain natriuretic peptide-45. Immunoreactive porcine brain natriuretic peptide was detectable in various tissues of the rat, and high concentrations of immunoreactive porcine brain natriuretic peptide were found in the brain and cardiac atrium, with the highest level in the hypothalamus (159±30 fmol/gram wet tissue, mean±SEM, n=4). Reverse phase high performance liquid chromatography showed that the immunoreactive porcine brain natriuretic peptide of the whole brain and heart extracts eluted mainly at an identical position to synthetic porcine brain natriuretic peptide-26. These findings indicate that porcine brain natriuretic peptide-like substance, distinct from rat brain natriuretic peptide, is present in high concentrations in the rat brain and cardiac atrium.  相似文献   
84.
The thyroid gland synthesizes thyroxine (T4), which passes through the larval tadpole's circulatory system. The enzyme type II iodothyronine deiodinase (D2) converts thyroxine (T4) to the active hormone 3,5,3'-triiodothyronine (T3) in peripheral tissues. An early response to thyroid hormone (TH) in the Xenopus laevis tadpole is the stimulation of cell division in cells that line the brain ventricles, the lumen of the spinal cord, and the limb buds. These cells express constitutively high levels of D2 mRNA. Exogenous T4 induces early DNA synthesis in brain, spinal cord, and limb buds as efficiently as T3. The deiodinase inhibitor iopanoic acid blocks T4- but not T3-induced cell division. At metamorphic climax, both TH-induced cell division and D2 expression decrease in the brain. Then D2 expression appears in late-responding tissues including the anterior pituitary, the intestine, and the tail where cell division is reduced or absent. Therefore, constitutive expression of D2 occurs in the earliest target tissues of TH that will grow and differentiate, while TH-induced expression of D2 takes place in late-responding tissues that will remodel or die. This pattern of constitutive and induced D2 expression contributes to the timing of metamorphic changes in these tissues.  相似文献   
85.
Photoacoustics and high frequency ultrasound stands out as powerful tools for neurobiological applications enabling high-resolution imaging on the central nervous system of small animals. However, transdermal and transcranial neuroimaging is frequently affected by low sensitivity, image aberrations and loss of space resolution, requiring scalp or even skull removal before imaging. To overcome this challenge, a new protocol is presented to gain significant insights in brain hemodynamics by photoacoustic and high-frequency ultrasounds imaging with the animal skin and skull intact. The procedure relies on the passage of ultrasound (US) waves and laser directly through the fissures that are naturally present on the animal cranium. By juxtaposing the imaging transducer device exactly in correspondence to these selected areas where the skull has a reduced thickness or is totally absent, one can acquire high quality deep images and explore internal brain regions that are usually difficult to anatomically or functionally describe without an invasive approach. By applying this experimental procedure, significant data can be collected in both sonic and optoacoustic modalities, enabling to image the parenchymal and the vascular anatomy far below the head surface. Deep brain features such as parenchymal convolutions and fissures separating the lobes were clearly visible. Moreover, the configuration of large and small blood vessels was imaged at several millimeters of depth, and precise information were collected about blood fluxes, vascular stream velocities and the hemoglobin chemical state. This repertoire of data could be crucial in several research contests, ranging from brain vascular disease studies to experimental techniques involving the systemic administration of exogenous chemicals or other objects endowed with imaging contrast enhancement properties. In conclusion, thanks to the presented protocol, the US and PA techniques become an attractive noninvasive performance-competitive means for cortical and internal brain imaging, retaining a significant potential in many neurologic fields.  相似文献   
86.
目的:探讨脑电生物反馈治疗对ADHD儿童心理、行为的影响。方法:对45例ADHD儿童采用脑电生物反馈训练。20次为一个疗程。治疗前和治疗后20、40次分别用症状评定量表进行比较。结果:接受20次训练的ADHD儿童注意、情感、活动水平、异常行为、学业等方面的问题都有明显好转;接受40次训练的ADHD儿童注意、情感、活动水平、异常行为、学业等方面的问题改善十分明显。P值〈0.01差异显著。结论:脑电生物反馈训练能有效地改善儿童注意、情感、活动水平、异常行为、学业等方面的问题。  相似文献   
87.
摘要 目的:探讨高压氧联合高频重复经颅磁刺激(rTMS)对重型颅脑损伤后意识障碍(DOC)患者促醒作用、神经电生理和脑损伤标志物的影响。方法:选取2021年6月~2023年6月期间安徽中医药大学附属六安医院收治的的80例重型颅脑损伤后DOC患者。根据随机数字表法分为对照组(n=40,高压氧治疗)和观察组(n=40,高压氧联合高频rTMS治疗)。对比两组疗效、促醒作用、神经电生理和脑损伤标志物水平变化情况。结果:观察组的临床总有效率高于对照组(P<0.05)。两组治疗4周后修订的昏迷恢复量表(CRS-R)、格拉斯哥昏迷量表(GCS)评分升高,观察组高于对照组(P<0.05)。两组治疗4周后脑干听觉诱发电位(BAFP)、四肢体感诱发电位(SEP)、脑电图(EEG)分级有所改善,观察组改善效果优于对照组(P<0.05)。两组治疗4周后髓鞘碱蛋白(MBP)、神经元特异性烯醇化酶(NSE)、S100β蛋白下降,观察组低于对照组(P<0.05)。结论:高压氧联合高频rTMS治疗可有效促醒重型颅脑损伤后DOC患者,还可改善神经电生理活动,减轻脑损伤程度。  相似文献   
88.
《Cell》2022,185(18):3375-3389.e21
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89.
Young rats (21 days old) made nutritionally iron deficient, by feeding them a semisynthetic diet containing skimmed milk for 5 weeks, had significantly lowered hemoglobin levels (5.2 +/- 4 g/100 ml). The nonheme iron content in caudate nucleus was decreased by 47%. The behavioral response of iron-deficient rats to apomorphine (2 mg/kg) and the density of 3,4-dihydroxyphenylethylamine (dopamine) D2 receptors, as measured by [3H]spiperone binding in caudate nucleus, were significantly reduced by 70 and 53%, respectively. The possibility that nutritional iron deficiency may affect protein content in brain was investigated by measuring the apparent concentration of proteins in caudate nucleus and nucleus accumbens from iron-deficient and control animals using two-dimensional gel electrophoresis. The data indicate that iron deficiency can affect content in these two brain regions. Significant changes in the content of 10 proteins were noted in the caudate nucleus and nucleus accumbens in iron-deficient rats. The albumin level was significantly increased in both regions studied, whereas the neuron-specific enolase level was increased in the nucleus accumbens and the glial fibrillary acidic protein level was reduced in the caudate nucleus. The significance of these protein content changes, as well as a reduction in content of a 94-kilodalton protein (a molecular size similar to that of the D2 dopamine receptor), remains to be established.  相似文献   
90.
Abstract: The subcellular distribution of acyl-CoA: sn -glycerol-3-phosphate O-acyltransferase between brain mitochondria and microsomes was investigated. The activities associated with purified rat brain mitochondrial and microsomal preparations could be distinguished by differences in their acyl-CoA specificity, products of acylation, and sensitivity to N -ethylmaleimide, trypsin, acetone, and polymyxin B. It was concluded that both brain mitochondria and microsomes possess the acyltransferase.  相似文献   
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